1. Field of the Invention
The present invention relates to a method and a device for the handling and processing of textile pieces, in particular but not exclusively, textile pieces of the type used for lingerie, for example for the production of brassieres.
2. Description of Related Art
Since textile fabric is usually supple, especially when delicate and very porous textiles such as those used for lingerie are concerned, it is very complicated to automate the manufacturing processes: it is very difficult for a machine to be able to pick up and arrange textile pieces with precision and reproducibility directly in front of the processing stations, such as those for cutting out or sewing, and to maintain them in position during the processing.
Nonetheless, various methods and devices have been proposed for handling textile pieces: usually the handling lacks precision and is limited to moving and picking up, etc.; in some cases, where the handling provides the possibility of completely automated processing for textile pieces, this concerns relatively small sized pieces, in fairly stiff and not very porous fabric.
The Levi Strauss document, U.S. Pat. No. 5,535,997, describes a procedure for de-stacking pieces of denim fabric from a pile using suction discs that can lift up one end of the top piece on the pile and then carry it onto a conveyor belt. Evidently, such a method would be impossible with the very lightweight and very porous fabrics used for lingerie.
The document, U.S. Pat. No. 5,238,237 describes the maintenance of porous textile pieces on a suction table and then picking them up using a needle device or a pneumatic device with a suction force greater than that of the suction table.
Sara Lee documents U.S. Pat. Nos. 5,165,355 and 5,040,475 describe a complex handling device for textile pieces intended for manufacturing tights, using a pneumatic system to pick up one piece from a pile of pieces and to carry it away for further processing.
The Pacific Dunlop document U.S. Pat. No. 4,896,618 also describes the use of suction means to pick up elastic strips for textile pieces intended for manufacturing panties, in order to place the pieces in various pleating and stretching devices that then carry the piece to the sewing stations. Such a method is very specific and is restricted to a single type of garment only, since it requires the presence of elastic strips that can be picked up by suction and furthermore cannot easily be adapted to different shapes and sizes.
Document U.S. Pat. No. 4,756,261 is of greater interest, providing information about setting the textile pieces at a precise orientation, picking them up and carrying them using a robot arm, still maintaining this orientation, until they reach a workstation where they are processed, for example sewn. The robot arm is equipped with a pick-up head with a suction plate that applies a very precise vacuum action (approximately 0.2 atmosphere) through specially adapted holes, to pick up and move the piece. However, as in the case of document U.S. Pat. No. 5,535,997 described hereabove, this is possible because it involves lifting and carrying pieces of “denim” fabric intended for shirt or trouser pockets. It would be impossible to use such a device for very porous textiles such as those used for lingerie.
The same observations are applicable to document U.S. Pat. No. 4,498,404, describing a perforated table connected to negative or positive pressure means, on which textile pieces can be placed, while a handling arm equipped with a suction plate picks up another piece, places it on top of the first piece and then carries the two superposed pieces to a sewing station.
Thus, all the above documents seem to demonstrate that textile piece handling using suction plates is possible as long as the textile is not very porous, as is the case with “denim” cloth, but not for the case of lingerie, manufactured with very lightweight, very supple fabrics, and sometimes lace.
For these fabrics, another research approach has been tried, as shown for example in document FR 2820290, describing how to cut out a piece in very supple fabric, using a temporary stiffening method by attaching it to a support sheet, for example in silicone coated paper, using hot calendering. Other temporary stiffening methods for textile pieces have also been proposed, for example, fixation by passing the fabric through a bath of stiffening product, or freezing, etc. In all these cases, this involves the addition of a supplementary stage that adds to the cost, and which is then doubled because of a stage needed for removing the temporary stiffening. Moreover, these stiffening methods are not without harmful consequences for very delicate fabrics like lace, which may be used for lingerie, and therefore these methods are not really suited to this field.
Therefore, since no really satisfactory methods have been discovered, the manufacture of certain lightweight textile articles such as lingerie remains an essentially manual operation, and is consequently expensive.